Refrigerant path holes in a rotary compressor

Abstract

In a rotary compressor, S1>S3, S2>S3, and S2′>S3′ are satisfied when a sectional area of a refrigerant path hole on a lower endplate is S1, a sectional area of the refrigerant path hole in a lower cylinder is S2, a sectional area of the refrigerant path hole on an intermediate partition plate is S3, an area in which a section of the refrigerant path hole on the lower end plate and a section of the refrigerant path hole in the lower cylinder overlap each other is S2′, and an area in which a section of the refrigerant path hole in the lower cylinder and a section of the refrigerant path hole on the intermediate partition plate overlap each other is S3′.

What is claimed is: 
     
       1. A rotary compressor which includes a sealed vertically-placed cylindrical compressor housing which is provided with a discharge pipe that discharges a refrigerant in an upper portion thereof, and which is provided with an upper inlet pipe and a lower inlet pipe that suction the refrigerant in a lower portion of a side surface thereof, an accumulator which is fixed to a side portion of the compressor housing and is connected to the upper inlet pipe and the lower inlet pipe, a motor which is disposed in the compressor housing, and a compressing unit which is disposed below the motor in the compressor housing, is driven by the motor, suctions and compresses the refrigerant from the accumulator via the upper inlet pipe and the lower inlet pipe, and discharges the refrigerant from the discharge pipe, and in which the compressing unit includes an annular upper cylinder and an annular lower cylinder, an upper end plate which blocks an upper side of the upper cylinder and a lower end plate which blocks a lower side of the lower cylinder, an intermediate partition plate which is disposed between the upper cylinder and the lower cylinder and blocks the lower side of the upper cylinder and the upper side of the lower cylinder, a rotation shaft which is supported by a main bearing unit provided on the upper end plate and a sub-bearing unit provided on the lower end plate, and is rotated by the motor, an upper eccentric portion and a lower eccentric portion which are provided with a phase difference from each other in a rotation shaft, an upper piston which is fitted to the upper eccentric portion, revolves along an inner circumferential surface of the upper cylinder, and forms an upper cylinder chamber in the upper cylinder, a lower piston which is fitted to the lower eccentric portion, revolves along an inner circumferential surface of the lower cylinder, and forms a lower cylinder chamber in the lower cylinder, an upper vane which protrudes from an upper vane groove provided in the upper cylinder in the upper cylinder chamber, abuts against the upper piston, and divides the upper cylinder chamber into an upper inlet chamber and an upper compression chamber, a lower vane which protrudes from a lower vane groove provided in the lower cylinder in the lower cylinder chamber, abuts against the lower piston, and divides the lower cylinder chamber into a lower inlet chamber and a lower compression chamber, an upper end plate cover which covers the upper end plate, forms an upper end plate cover chamber between the upper end plate and the upper end plate cover, and has an upper end plate cover discharge hole that allows the upper end plate cover chamber and the inside of the compressor housing to communicate with each other, a lower end plate cover which covers the lower end plate and forms a lower end plate cover chamber between the lower end plate and the lower end plate cover, an upper discharge hole which is provided on the upper end plate and allows the upper compression chamber and an upper end plate cover chamber to communicate with each other, a lower discharge hole which is provided on the lower end plate and allows the lower compression chamber and a lower end plate cover chamber to communicate with each other, and a refrigerant path hole which penetrates the lower end plate, the lower cylinder, the intermediate partition plate, the upper cylinder, and the upper end plate, and communicates with the lower end plate cover chamber and the upper end plate cover chamber, the compressor comprising:
 an upper discharge valve which opens and closes the upper discharge hole; 
 a lower discharge valve which opens and closes the lower discharge hole; 
 an upper discharge valve accommodation concave portion which is provided on the upper end plate and extends in a shape of a groove from a position of the upper discharge hole; and 
 a lower discharge valve accommodation concave portion which is provided on the lower end plate and extends in a shape of a groove from a position of the lower discharge hole, 
 wherein the lower end plate cover is formed in a shape of a flat plate, 
 wherein a lower discharge chamber concave portion is formed on the lower end plate to overlap the lower discharge hole side of the lower discharge valve accommodation concave portion, 
 wherein the lower end plate cover chamber is configured of the lower discharge chamber concave portion and the lower discharge valve accommodation concave portion, wherein the lower discharge chamber concave portion is formed within a fan-shaped range between straight lines that link the center of a first insertion hole and the center of a second insertion hole which are adjacent to each other among a plurality of insertion holes into which a fastening member that fastens the lower end plate cover, the lower end plate, the lower cylinder, the intermediate partition plate, the upper cylinder, the upper end plate, and the upper end plate cover is inserted and which are provided on a circumference of a concentric circle around the rotation shaft to penetrate the lower end plate, the lower cylinder, the intermediate partition plate, the upper cylinder, and the upper end plate, and the center of the sub-bearing unit, 
 wherein the refrigerant path hole communicates with the lower discharge chamber concave portion while at least a part thereof overlaps the lower discharge chamber concave portion, and is positioned between the lower vane groove and the first insertion hole in the lower cylinder, and between the upper vane groove and the first insertion hole in the upper cylinder, and 
 wherein S 1 >S 3 , S 2 >S 3 , and S 2 ′>S 3 ′ are satisfied when a sectional area of the refrigerant path hole on the lower end plate is S 1 , a sectional area of the refrigerant path hole in the lower cylinder is S 2 , a sectional area of the refrigerant path hole on the intermediate partition plate is S 3 , an area in which a section of the refrigerant path hole on the lower end plate and a section of the refrigerant path hole in the lower cylinder overlap each other is S 2 ′, and an area in which a section of the refrigerant path hole in the lower cylinder and a section of the refrigerant path hole on the intermediate partition plate overlap each other is S 3 ′. 
 
     
     
       2. The rotary compressor according to  claim 1 ,
 wherein the sectional area of the refrigerant path hole on the lower end plate Si and the sectional area of the refrigerant path hole in the lower cylinder S 2  satisfy S 1 ≥S 2 . 
 
     
     
       3. The rotary compressor according to  claim 1 ,
 wherein the compressing unit further includes a connection hole that carries a liquid refrigerant from an injection pipe, and an injection hole which injects the liquid refrigerant that has gone through the connection hole into the compression chamber, on the intermediate partition plate, and 
 wherein the center of the injection hole is provided within a fan-shaped range that is defined by 40 degrees from a center line of either of the upper or lower vane grooves in a circumferential direction of the rotation shaft. 
 
     
     
       4. The rotary compressor according to  claim 1 ,
 wherein the refrigerant path hole on the lower endplate and the refrigerant path hole on the upper end plate have the same diameter, and the refrigerant path hole in the lower cylinder and the refrigerant path hole in the upper cylinder have the same diameter. 
 
     
     
       5. The rotary compressor according to  claim 1 ,
 wherein the plurality of insertion holes have the same diameter of the refrigerant path hole in at least one of the lower end plate, the lower cylinder, the intermediate partition plate, the upper cylinder, and the upper end plate. 
 
     
     
       6. The rotary compressor according to  claim 1 ,
 wherein a spot facing or a cutout is provided on an end surface of the refrigerant path hole in at least one of: the lower end plate, the lower cylinder, the intermediate partition plate, the upper cylinder, and the upper end plate. 
 
     
     
       7. The rotary compressor according to  claim 1 ,
 wherein relational expressions, S 5 >S 3 , S 4 >S 3  and S 4 ′>S 3 ″, are satisfied when a sectional area of the refrigerant path hole in the upper cylinder is S 4 , a sectional area of the refrigerant path hole on the upper end plate is S 5 , an area in which a section of the refrigerant path hole on the upper end plate and a section of the refrigerant path hole in the upper cylinder overlap each other is S 4 ′, and an area in which a section of the refrigerant path hole in the upper cylinder and a section of the refrigerant path hole on the intermediate partition plate overlap each other is S 3 ″. 
 
     
     
       8. The rotary compressor according to  claim 7 , wherein the sectional area of the refrigerant path hole in the upper cylinder S 4  and the sectional area of the refrigerant path hole on the upper end plate S 5  satisfy S 5 ≥S 4 .